Vacuum steam heating system



Feb. 16, 1932. l. c. JENNINGS VACUUM STEAM HEATING SYSTEM ATTORNEY 11v VENTOR jfizz a C. 7537/21 W Filed Nov. 16, 1926 Fatented Feb. 16, 1932 PATENT OFFICE IRVING C. JENNINGS, OF SOUTH NORWALK, CONN EGTICUT VACUUM STEAM HEATING SYSTEM Application filed November 16, 1926. Serial No. 148,745.

The object of this invention is to improve the operation and safety of steam heating systems particularly vacuum steam heating systems. To this'end the invention consists of the improvements hereafter described and illustrated in the accompanying sheet of drawings, in which Fig. 1 is a diagrammatic view illustrating a vacuum steam heating system with my improvements applied thereto;

Fig. 2 is a detail illustrating a slightly modified form of connection, and

Fig. 3 is a detail hereinafter referred to.

The vacuum steam heating system illus- 1 trated in the drawings comprises a steam boiler 1, which is connected by steam supply pipes a to the radiators 8 in the building or space to be heated. A shut off or control valve 11 is arranged in this pipe near the boiler. This shutoff or control valve is used to regulate theflow of steam to the radiators and may be opened wide in cool weather and closed or cracked in warm weather or at night. Each radiator 3 is provided at its outlet end with a steam trap 10. The radiators 3 are connected by return pipes 5 to a separating tank 2 so that the condensate will flow into said tank.

A pumping apparatus P is connected to said receiving tank to exhaust the air and gas therefrom and force the same out into the atmosphere through an air escape pipe 7 having a check valve 17 and to take the water from the bottom of the tank 2 and return the same to the boiler or hot well through a pipe 6.

The pumping apparatus is driven by an electric motor and the operation thereof may be automatically controlled by a vacuum regulator 12 and a float control 13. Two

pumps preferably are employed, viz. a hydro-turbine air pump and a centrifugal water pump. The details of the pumps and the connections between the same and the separating tank are shown in a patent granted to me December 29, 1925, No. 1,567 ,148, pumping apparatus. The mechanisms thus far described constitute an improved vacuum steam heating system.

In describing said system, I use the term supply side of the system to denote that part of the system including the supply pipes 4, control or shut-off valve 11, the radiators, and all parts of the system up to the steam traps 10. By the term return side of the system, I mean'that part of the system which extends from said steam traps back through the return pipes, the separating tank, the water pump and the feed pipe to the boiler.

In the operation of such a system, the radiators are supplied with steam from the boiler. The steam traps 1O permit gas and water to flow to the return side of the system, but prevent the flow of steam.

The condensate flows from the radiators down through the return pipes 5 into the separating tank 2. The air pump normally maintains a vacuum in the radiators and the return side of the system up to the pumping mechanism and withdraws anyair and gas that may get into the system and forces the same out lnto the atmosphere. The water pump returns the condensed water back to the boiler. The advantages of the vacuum steam heating system are well known and need not be set forth.

In operating such systems, considerable trouble has been experienced in getting the condensate back to the boiler or hot-well, when the steam pressure is allowed to drop due to the banking of the fire, shutting down of an oil burner, or when the shut-off or control valve is closed or partly closed. Under these conditions a vacuum is apt to be produced in the supply side of the system due to the condensation of the steam in the radiators and in the supply pipes. This vacuum may be so high that a large amount of water will be held up in the system. When this occurs, the pumping mechanism even though it is provided with float and vacuum control, cannot return the water to the boiler or the hot-well, because in order to do this, the water has first to go back to the pumping mechanism and this it cannot do because it is held up in the radiators by the higher vacuum in the supply side of the system which is greater than the vacuum which the pumping mechanism normally can create. This high vacuum cannot be transmitted back to the pumping mechanism because of water seals in the radiators and piping and also on account of the steam-traps. Under these conditions, so little water may be left in the boiler that the water line will be below the safe level and should the fire be started again suddenly as may occur when an automatic oil burner is turned 011, damage to the boiler or even an explosion may be caused, when the boiler, having built up a steam pressure suiiicient to release the water in the supply side of the system, allows the pump suddenly to inject all of this water into the boiler.

To overcome this danger, I provide a shunt pipe line 8 between the return side of the system and the supply side of the system beyond the control valve. This pipe 8 is provided with means for allowing a flow from the return side of the system to the supply side ot the system. This means comprises an automatically opening and closing valve such as a thermostatic valve or a check valve as 9 included in the shunt pipe line 8 and opening towards the boiler. Although the shunt pipe line may be connected at any convenient points in the two parts of the system, it is preferably connected to the top of the separating tank 2 and to the steam supply pipe 4 near the boiler as shown in Fig. 1 or as shown in Fig. This shunt pipe line and check valve do not interfere with the the normal operation of the parts because when normal pressure is maintained in the supply side of the system there can be no flow therethrough. But when the conditions previously recited are encountered and a vacuum is produced in the supply side of the system, this vacuum will be relieved by the flow through pipe 8 and the check valve 9 and the pressures in the supply and return sides of the system will be balanced and the water in the system will flow down the return pipes 5 back into the separating tank 2. This insures that when the boiler and pump are again started in operation, the pump will immediately commence to take the water from the separating tank and return the same to the boiler and insures that the parts will start in operation properly.

By providing means to allow the balancing of the pressures as above described, the operation of the system is rendered safe under all conditions.

The details and arrangements herein shown and described may be greatly varied by a skilled mechanic without departing from the scope of my invention as expressed in the claims. 1

Having thus described my invention, what I claim and desire to secure by Letters Patent is 1. In a vacuum steam heating system, the combination of a boiler, radiators, a supply 'pipe extending from the boiler and connected to the radiators, a valve in the supply pipe controlling the supply of steam, return pipes, a separating tank to which the return pipes connect, a pumping mechanism, a shunt pipe line extending from the return side of the system to the supply pipe at a point beyond the valve, and means in said shunt pipe line allowing a flow only from the return side of the system to the supply pipe.

3. In a vacuum steam heating system, the combination of a boiler, radiators, a supply pipe extending from the boiler and connected I to the radiators, a valve in the supply pipe controlling the supply of steam, return pipes, a separating tank to which the return pipes connect, a pumping mechanism, a shunt pipe line extending from the return side of the system to the supply pipe at a point beyond the valve and a check valve in said shunt pipe line opening towards the supply side of the system.

In testimony whereof I have hereunto aflixed my signature.

IRVING C. JENNINGS. 

